Laser local dimming for projectors and other lighting devices including cinema, entertainment systems, and displays

ABSTRACT

Light from an array of laser light sources are spread to cover the modulating face of a DMD or other modulator. The spread may be performed, for example, by a varying curvature array of lenslets, each laser light directed at one of the lenslets. Light from neighboring and/or nearby light sources overlap at a modulator. The lasers are energized at different energy/brightness levels causing the light illuminating the modulator to itself be modulated (locally dimmed). The modulator then further modulates the locally dimmed lights to produce a desired image. A projector according to the invention may utilize, for example, a single modulator sequentially illuminated or separate primary color modulators simultaneously illuminated.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 15/272,638, filed Sep. 22, 2016, which is a continuation ofU.S. Pat. No. 9,478,193 issued Oct. 25, 2016 (formerly U.S. patentapplication Ser. No. 14/004,406, filed on Sep. 10, 2013), which is theU.S. national stage of International Patent ApplicationPCT/US2012/029115 filed on Mar. 14, 2012, which claims priority to U.S.Patent Provisional Application No. 61/452,641, filed Mar. 14, 2011, allof which are hereby incorporated by reference in their entirety.

BACKGROUND OF THE INVENTION

The present invention relates to laser imaging systems and moreparticularly to laser projection systems and local dimming thereof.

Various projection systems are known including cinema projectors andhome theater. Other projections of various styles are known forilluminating modulators in, for example, LCD displays. These projectionsystems are generally 2D systems, but growing in popularity are variousconfigurations that implement 3D stereoscopic projectors.

3D stereoscopic projection include Anaglyph, Linear Polarization,Circular Polarization, Shutter Glasses, and Spectral Separation.Anaglyph is the oldest technology, and provides left/right eyeseparation by filtering the light through a two color filter, commonlyred for one eye, and cyan for the other eye. At the projector, the lefteye image is (commonly) filtered through a red filter, and the rightimage filtered through a cyan filter. The eyewear consists of a redfilter for the left eye, and a cyan filter for the right eye. Thismethod works best for black and white original images, and is not wellsuited for color images.

Linear Polarization 3D provides separation at the projector by filteringthe left eye through a linear polarizer (commonly) oriented vertically,and filtering the right eye image through a linear polarizer orientedhorizontally. The eyewear consists of a vertically oriented linearpolarizer for the left eye and a horizontally oriented polarizer for theright eye. The projection screen must be of the polarization preservingtype, commonly referred to as a “silver screen” because of itsdistinctive color. Linear Polarization allows a full color image to bedisplayed with little color distortion. It has several problems, theseinclude the need for a silver screen which is expensive, fragile, andnot uniform. Another problem is that the viewer must keep his headoriented vertically to avoid crosstalk from one eye to another.

Circular Polarization 3D was invented to address the problem ofrequiring the viewer to keep his head oriented vertically. CircularPolarization provides separation at the projector by filtering the lefteye image through a (commonly) left handed circular polarizer, andfiltering the right eye image through a right handed circular polarizer.The eyewear consists of a left handed circular polarizer for the lefteye and a right handed circular polarizer for the right eye. A silverscreen is also needed for this approach.

Shutter Glasses provides separation by multiplexing the left and rightimages in time. A filter for separation at the projector is notrequired. The eyewear consists of Shutter Glasses. These are activeglasses that electronically shutter the lens in synchrony with theprojector frame rate. The left eye image is first displayed, followed bythe right eye image etc. Since having a direct wired connection to theGlasses in a theatre is impractical, a wireless or infrared signalingmethod is used to provide a timing reference for the left/right eyeshuttering. This method requires an IR or RF transmitter in theauditorium. The Shutter Glasses are expensive and hard to clean, requirebatteries that must be frequently replaced, and are limited in theirswitching rate. Shutter glasses are only practical for use with D-Cinemaor other electronic projection systems since very few film projectorsprovide the signal required to synchronize the shutter glasses with theframe rate. The method does not require a silver screen. SpectralSeparation provides separation at the projector by filtering the leftand right eye spectrally. The system differs from anaglyph in that thefilters for the left and right eye each pass a portion of the red,green, and blue spectrum, providing for a full color image. The bandpass spectrum of the left eye filter is complementary to the band passspectrum of the right eye filter. The eyewear consists of filters withthe same general spectral characteristics as are used in the projector.While this method provides a full color image, it requires colorcompensation to make the colors in the left and right eye match thecolors that were present in the original image, and there may be a smallreduction in the color gamut compared to the gamut of the projector.

All of the above methods for providing left/right eye separation for a3D Stereoscopic presentation can be used with either two projectors (onefor the left eye and one for the right eye), or may be used with asingle D-Cinema projector system. In a typical projection system, theleft and right images are time multiplexed. Except for the ShutterGlasses case where no projection filters are required, this means thatthe projection filters must change at the L/R multiplex frequency. Thiscan be done with either a filter wheel in the projector synchronized tothe multiplex frequency, or with an electronically switched filter.

SUMMARY OF THE INVENTION

The present inventor has realized the need to improve performance,including contrast, in projection systems. The present inventionincludes specific arrangements of lighting and optical components thatimplement local dimming and increase performance of a projector orillumination system.

In one embodiment, the present invention provides a display device,comprising a plurality of laser light sources directed at a spreaderconfigured to spread light from each light source into an overlappingpattern on a primary modulator, and a processing device configured tocalculate an energization level of each laser light source based on animage signal such that the overlapping pattern is locally dimmed. Thedisplay may further comprise a secondary modulator configured tomodulate the laser lights prior to illuminating the primary modulator.

The locally dimmed overlapping pattern may be configured to cause areasof the modulator corresponding to darker regions of an image carried bythe image signal to have less illumination than areas of the modulatorcorresponding to brighter regions.

The locally dimmed overlapping pattern may be configured, on average, tocause areas of the modulator corresponding to darker regions of an imagecarried by the image signal to have less illumination than areas of themodulator corresponding to brighter regions.

The locally dimmed overlapping pattern comprises overlapping instancesof combined primary lights and/or overlapping instances of more than 3primary light colors. The overlapping pattern may comprise overlappinginstances of red, green, blue, and cyan light colors. The overlappingpattern may comprise a sequential illumination of the modulator withprimary lights such that the overlapping pattern comprises overlappinginstances of a first primary light in a first time period, a secondprimary light in a second time period, and a third primary light in athird time period. The primary lights may comprise at least one of red,green, blue, and yellow, cyan.

The processor may be further configured to calculate an energizationlevel for each pixel of the modulator based on the image signal and theenergization level of the light sources. The energization level forpixels of the modulator may be based, at least in part, on a Light FieldSimulation (LFS) of the overlapping pattern.

The display may comprise an optical block configured to direct lightbeams from the light sources through spreaders configured to spread andcause overlap between adjacent and/or nearby light beams and then ontothe modulator.

The display may further comprise a second plurality of laser lightsources directed at a second spreader configured to spread light fromeach light source of the second plurality into an overlapping pattern ona second modulator, and a third plurality of laser light sourcesdirected at a third spreader configured to spread light from each lightsource of the third plurality into an overlapping pattern on a thirdmodulator. The plurality of light sources may comprise a plurality ofonly first primary light sources, the second plurality of laser lightsources may comprise a plurality of only second primary light sources,and the third plurality of light sources may comprise only third primarylight sources.

The present invention is embodied as a device, apparatus, method,system, or other forms consistent with that provided herein. Portions ofthe device, method, system or other form of the invention may beconveniently implemented in programming on a general purpose computer,or networked computers, and the results may be displayed on an outputdevice connected to any of the general purpose, networked computers, ortransmitted to a remote device for output or display. In addition, anycomponents of the present invention represented in a computer program,data sequences, and/or control signals may be embodied as an electronicsignal broadcast (or transmitted) at any frequency in any mediumincluding, but not limited to, wireless broadcasts, and transmissionsover copper wire(s), fiber optic cable(s), and co-ax cable(s), etc.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings, wherein:

FIG. 1 is a drawing of a laser light source illuminating a modulatoraccording to an embodiment of the present invention;

FIG. 2 is a drawing of a laser light source bundle illuminating amodulator according to an embodiment of the present invention;

FIG. 3 is a drawing of a light source bundle and a multiple redirectionblock according to an embodiment of the present invention;

FIG. 4 is a drawing illustrating a spreader and an illumination patternaccording to an embodiment of the present invention;

FIG. 5 is a drawing illustrating various example illumination patternsaccording to the present invention;

FIG. 6 is a drawing illustrating a system and processing associated withvarious embodiments of the present invention; and

FIG. 7 is a drawing illustrating a retrofit of a projection deviceaccording to an embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings, wherein like reference numerals designateidentical or corresponding parts, and more particularly to FIG. 1thereof, there is illustrated a laser light source 105 illuminating amodulator 120 according to an embodiment of the present invention. Thelaser light is passed through a spreader 110 to cause the light tospread (115). The spreading light 115 then illuminates an area of themodulator 120 that is larger than the area of light produced by thelaser light source and any “native” spreading that might have occurredin the light path between the light source and modulator if the spreaderwere not present. The increased area of illumination by a single lightsource allows the use of multiple, and/or multiple overlapping laserlight sources to illuminate the entire modulator.

FIG. 2 is a drawing of a laser light source bundle 205 illuminating amodulator 225 according to an embodiment of the present invention. Here,several of the bundled laser light sources 205 are energized andproducing light. The light is spread by a spreader 210 causing the lightto spread (220). The spreading light 220 then illuminates the modulator225. As illustrated, with additional laser light energizations, theentire modulator 225 is illuminated. At differentenergization/brightness levels, illumination of the modulator is locallydimmed.

In one embodiment, two or more of the lights provided by the illustratedlight sources may, instead of being separate sources, may be produced bya common light source and a splitter or other separating opticalelement/elements. In one embodiment, a series of light sources are eachsplit multiple times to provide a full array of light beams. In oneembodiment, the light beams provided by a common light source may beindividually modulated with the use of liquid crystal panel andenergization of specific liquid crystal cells that the individual beamsare incident. The modulation of an individual beam may be accomplishedby, for example, a combination of the energization level of the lightsource and the energization level of liquid crystal cells upon which thelight or portions thereof are incident.

Turning back the exemplary embodiment of FIG. 2, additional lightsources may also be energized. For example, all of the light sources maybe simultaneously energized. The bundled laser light sources 205 may be,for example, any primary color in a projection system. The bundled lightsources 205 may be, for example, a set of single colored laser lightsources such as any of red, green, or blue, in an RGB system, or any ofyellow, magenta, or cyan or other primary colors.

The bundled light sources may also be a mixed set of primary colors suchas a set of red, green, and blue laser light sources. Depending on otherfactors of projector design, the Red green and blue laser may beprogrammed to be on simultaneously, or to alternate energization in atime sequence (e.g., T1 energize red laser, T2 energize green laser, andT3 energize blue laser). The time period may be sequential, repeated, orinterspersed with other intervals, such as blanking intervals. The timeperiod may be adjusted, such that one of the colors may have a longertime period than others, and the time periods for one, more, or all ofthe colors may be variable.

In one embodiment, the time periods (or number of time periods) for eachcolor are determined based on image data. For example, in darker scenes,the time periods may be decreased. In scenes with specific colorrequirements, the predominate colors may be increased (e.g., blue skyscenes may utilized an increased blue time period). In concert with suchtime period adjustments, flash periods may be correspondingly adjusted.

In another embodiment, the time period may also be adjusted based oncharacteristics of the projector or light sources themselves. Forexample, projectors with higher light loss in a specific color mayincrease the time period for the color. A malfunctioning laser or laserbank may also be compensated for by adjusting the time period or otherparameter of laser energization. Timing of energization of individuallasers of the same color may also vary within a correspondingenergization time period. Such timing may be for example to match anenergization pattern of the modulator(s) or other elements (e.g.,filters, shutters, polarizers, etc), including mechanical movementwithin the image chain.

Any form of Pulse Width Modulation (PWM) may be utilized. However, afrequency at which the PWM occurs must be considered. In the case of aDMD modulator implementation the PWM frequency must not match the DMDmodulator frequency, which could cause either no benefit (laser on onlywhen mirror is reflecting into the image chain) or no illumination(laser not on when positioned to reflect into the image chain). In oneembodiment, PWM of the lasers is implemented at a frequency much higherthan a switching frequency of the modulator(s) in the projector ordisplay (e.g., greater than 400 MHz for DMD, or greater than 60 FPS on acommon LCD).

Amplitude modulation of the lasers may also be utilized.

FIG. 3 is a drawing of a light source bundle 305 and a redirection block335 according to an embodiment of the present invention. As illustrated,the re-direction block 335 is a multiple re-direction block in that itreceives lights from a plurality of light sources (light source bundle305) and re-directs individual beams of the light sources toward amodulator 320. The re-direction is provided by optical elements (e.g.,optical elements 330 and 332). The optical elements may be, for example,a reflector or a beam splitter (e.g., one portion of the split beamdirected towards modulator 320, the other portion towards a secondmodulator) (e.g., a splitter configured to pass one light beam andreflect another into a same or similar optical path). The opticalelements may be mirrors or silverized surfaces embedded in the opticalblock. The optical elements may also be an impression or otherpermutation in the optical block that causes a total internalreflection. More than one optical element (or reflector) may be utilizedin each optical path.

A spreader 310 is also shown and intended to illustrate the case of anon or low spreading light sources (e.g., laser light sources) which arethen spread to illuminate the modulator 320. However, as with all suchexemplary embodiments described herein, such configurations are notlimited to laser light implementations. And, a selection of energizedlight sources are shown for illustrative purposes. However, as discussedabove, all of the light sources may be energized, or a selection may beenergized, they may be energized at different times (e.g. Pulse WidthModulation PWM, and/or they may be energized at different energy levels(e.g., amplitude modulation).

In one embodiment, the redirection optics and spreader/spreadingfunction are combined. For example, the reflectors may also include anyof lenslets, diffusers (e.g., holographic), or other optics to performspreading which may be utilized to replace the function of spreader 310.

Typically, the selected energized light sources will provide enoughcoverage for the entire modulating surface of the modulator 320 ifbrightness is needed (e.g., for completely dark or black portions of animage, the modulator may not need to be illuminated). Optionally, incases where a totally dark region of an image or scene is near to onethat is partially or fully illuminated (e.g., either spatially ortemporally) some illumination may be provided to the dark region (whichmay take the form of a gradual fade to black). In one embodiment, a fadeto black rate is adjusted in areas within the “dark” region based onimage data such as temporal image changes, the relative brightnesses ofnearby regions, or other factors (including optical performance of oneor more components of the imaging system).

In one embodiment, a broken or malfunctioning light source is detectedand algorithms recognizing the failure also adjust internal parameterssuch as fade to black rates or the brightness/modulations of other lightsources to compensate for the malfunction. Sensors in the image chaincan be placed to provide real-time performance feedback and anynecessary adjustments to improve display performance, or compensate formalfunctions, can be made on-the-fly in real-time during image displayor projection.

In one embodiment the optical pathlengths of the light sources arematched. For example, when using an optical block such as thatillustrated in FIG. 3, the light sources may be moved upstream ordownstream relative to each other based on the relative distancesbetween the light sources and their corresponding redirection element(e.g., light source for reflector 330 may be downstream relative toreflector 332). The lightpaths may be equalized by adjusting otherelements in the optical path as well.

FIG. 4 is a drawing illustrating a spreader 410 and an illuminationpattern 420 according to an embodiment of the present invention. Thespreader 410 comprises a series of spreader elements (e.g., spreaderelement 412). The spreader elements are, for example, disposed on or ina substrate 416. The spreader elements may be constructed, for example,using layers of lens materials, diffusers, 414, and possibly shutters,light guides, and/or optical dividers (not shown). In one embodiment,the spreader element comprises a lens subelement targeted by one or morelight sources/beams, followed by a diffuser subelement, and the diffusersubelement including reflective optical walls that direct the spread ofthe light in a manner that fills a predetermined illumination pattern ona downstream modulator.

In one embodiment, the spreader is constructed using a holographicmaterial. The holographic material diffuses the light at apre-determined angle or with a predetermined Point Spread Function(PSF). Compared to a typical diffuser, the holographic diffuser emitslight at a controlled angle and/or in a limited PSF. In one embodiment,the spreader is a single layer of a holographic diffuser, and in otherembodiments, sub-elements of the diffuser comprise holographic material.The holographic diffuser or materials may be used in conjunction withother optical elements.

Typically, the spreader causes the light to spread in an evendistribution. However, embodiments include sub-elements that haveproperties that vary in order to implement an illuminating pattern thatis not homogeneous or isotropic.

The illumination pattern 420 illustrates an exemplary mixing of lightfrom the various light sources which includes an overlap at edges ofadjacent light sources' illumination patterns. For example, illuminationarea 422 overlaps on its east-side with illumination pattern 422-E, onits south-side with illumination pattern 422-S, and on its southeastcorner with illumination pattern 422-SE. Illumination pattern 424overlaps with the eight illumination patterns surrounding illuminationpattern 424. All of the patterns together from the illumination patternon the modulator.

Preferably, the illumination patterns are proportional to a display orscreen size of the device or system by which the desired or resultingimages are viewed. In a 16:9 screen, the illustrated illumination areaswould themselves be of a shape have a 16:9 ratio. However, other sizes,shapes or relative ratios may be utilized.

FIG. 5 is a drawing illustrating various example illumination patternsaccording to the present invention. The illustrated illuminationpatterns include a black dot that indicates an approximate illuminationpattern that would occur without spreading from the light source. Theillumination patterns may be produced by natural spreading initiated bya reflector around each light source, natural spreading only, or, andparticularly in the case of laser light sources (either individual lightsources or split beams), spreading due mainly to a spreader element inthe upstream light path. Still, in each case, the black dot is providedfor reference.

Illumination pattern 532 is provided by a circular type of spreading orPoint Spread Function (PSF) of the light. Illumination pattern 534 isprovided by a rectangular-like spread function (e.g., spreader and/orPSF of the light). Illumination pattern 536 illustrates a mixed overlapwhere illumination areas in an interior of the entire illuminated areaare mixed more heavily (more overlap) compared to illumination areas atthe edges. The relative mixing between areas may be gradually changedacross the entire illuminated area either increasing or decreasingtowards a central area. Ultimately, such mixing is produced on a surfaceof a modulator or other component of an optical, display, or projectionsystem.

Although mainly shown for illustrative purposes as overlapping edges ofadjacent light sources/PSFs, the invention includes a wider footprint orPSF of each light source which may, for example, encompass central areasof the illumination pattern of a predetermined number of light sources.For example a light source may have a PSF that encompasses areasilluminated by 9 or more other light sources (e.g., example PSF 533)(e.g., more than just adjacent illuminated areas overlap). For example,the spreading of a first light source fully illuminates an areaimmediately surrounding a central point of the first light source'sillumination pattern, and fully illuminates an area immediatelysurrounding the central points of illumination by adjacent lightsources. Depending on the number of areas or light sources, this maycontinue for one or more levels. The first light source may then alsopartially illuminate areas immediately surrounding central points ofillumination by light sources adjacent to those whose illuminationpatterns are fully illuminated by the first light source.

FIG. 6 is a drawing illustrating a system 600 and processing associatedwith various embodiments of the present invention. An array of laserlight sources 605 provides narrowband illumination beams 608 which aredirected at an arrayed spreader which operates to spread the narrowbandlaser lights. The spread lights 615 then illuminate modulator 620.

Modulator 620 may be an LCD panel, a Digital Mirror Device (DMD), aliquid Crystal on Silicon (LCOS) chip, or other modulation/light valvedevices. The modulator selection may be decided based on otherarchitectural factors of the system being built. The modulator may betransmissive or reflective and may be oriented at an angle such that thepost-modulated light is reflected at an angle away from the upstreampath and toward downstream portions of the image chain.

Preferably, the illumination of modulator 620 comprises a locally dimmedillumination comprising an approximation of a desired image to bedisplayed. The approximation is determined, for example, from an imagesignal 640 carrying a representation of the desired image. Processor 650receives the image signal and determines the approximation andappropriate energization levels of the array of laser light sources 605to produce the approximation on modulator 620 (e.g., approximationmodule 655-1). The approximation includes calculations based on theamount of light spreading that occurs in the image chain, which willdepend on the optical characteristics of the spreader 610, and otherproperties of the system. The energization level of each individuallycontrollable light source (e.g., M light sources) is signaled to thelight sources (and may include additional driver hardware (not shown).

In embodiments where the light sources are grouped into colors oranother denomination, the approximation signals are calculated for eachgroup. The signals for each group likely contain some similarcharacteristics, and that commonality may be utilized to increaseefficiency of the processing for each group.

Modulation performed by the modulator 620 is implemented to account forthe illumination pattern incident on the modulator includingoverlapping, if any, of the illuminations originating from adjacent ornearby light sources. The modulations may be calculated by, for example,determining a simulation of the illumination field at the modulator andthen energizing the modulator to alter the illumination so as to fullymodulate the lights to contain the desired image when projected and/orfocused at a viewing location. The modulations may also be calculatedbased entirely on the image signal by calculating the laser energizationlevels and then applying a look-up table or other conversion (equation)using both the original image signal and laser energization levels. Themodulation signals include energization data for, for example, N pixelsof the modulator 620.

In one embodiment, L additional “midpoint” modulations are performed.The “midpoint” modulations may be implemented, for example, by amid-point modulator 612. The mid-point modulator may be, for example, agrayscale or color LCD panel, or, an array of optical switches (e.g.,the type of switches used for communication over fiber optic cable). Themid-point modulator is a secondary modulator configured to modulate thelaser lights prior to illuminating the modulator 620.

The mid-point modulator 612 may be positioned at a point after spreader610 but before the lights overlap. In one embodiment, mid-pointmodulator 612 is positioned at a point after overlapping has occurred.In one embodiment, the mid-point modulator is placed before the spreader(e.g., an optical switch embodiment would have high efficiency at thisposition). Energization of mid-point modulator 612 may include, forexample, the use of a Light Field Simulation (LFS) or other algorithmfor determining a preferred modulation at the location of mid-pointmodulator 612. The additional modulations provided by the mid-pointmodulator are taken into account by either LFS or other calculations andused for determining energization of modulator 620.

In one embodiment, a mid-point modulator is constructed of opticalswitches configured to selectively re-direct light from its primary areaon the modulator to another area on the modulator. A switch may have 2or more directions in which the light may be directed, and, in thisembodiment, the switch, for example, redirects light from “dark” areasof a modulator corresponding to dark portions of an image beingmodulated to “bright” areas. Corresponding changes in the LFS (or othermethods for determining energization) at the modulator, along withprogramming of the switches themselves, is implemented, for example, inprocessor 650.

FIG. 7 is a drawing illustrating a retrofit of a projection device 750according to an embodiment of the present invention. The projectiondevice includes a kernel having prisms for separating and recombiningcolored lights and modulators for modulating the colored lightsseparately. In one embodiment, separate banks of lasers are provided foreach of primary lights. For example, laser bank 705R producing modulated(locally dimmed) red light, laser bank 705G providing modulated greenlight, and laser bank 705B producing modulated blue light. The modulatedlights are then spread (begin spreading) via individual spreaders (e.g.,710R, 710B, and 710G), combined and input (e.g., via optics 720) intothe projector kernel, where they are separated, further modulated,re-combined, and then projected by a projection lens onto a viewingscreen.

In other embodiment, a single bank of lasers is provided with a set ofprimary color lights and a common spreader. A common spreader mayinclude separate or shared optics (e.g., an array of lenslets) thatcause the lights to spread. The lenslets may be designed to impart aPoint Spread Function (PSF) to each light such that the overlappingedges are faded compared to a central area of each individualillumination pattern causing the mixed lights to vary in a predeterminedfashion (e.g., vary smoothly from one illumination area to the next).Other PSFs may also be implemented.

Other embodiments include directly illuminating separate red, green, andblue modulators with corresponding red, green, and blue laser banks(bundles) and spreaders.

Although the present invention has been described herein with referenceto laser lights providing illumination, the invention may also bepracticed using broadband or broaderband light sources (e.g., LEDs,nanotube based light sources, etc). In describing preferred embodimentsof the present invention illustrated in the drawings, specificterminology is employed for the sake of clarity. However, the presentinvention is not intended to be limited to the specific terminology soselected, and it is to be understood that each specific element includesall technical equivalents which operate in a similar manner.

For example, when describing any part of the present invention, anyother equivalent device, or other device having an equivalent functionor capability, whether or not listed herein, may be substitutedtherewith. Furthermore, the inventors recognize that newly developedtechnologies not now known may also be substituted for the describedparts and still not depart from the scope of the present invention. Allother described items, including, but not limited to light sources,lasers, modulators, panels, processing devices, optical elements, etcshould also be considered in light of any and all available equivalents.

Portions of the present invention may be conveniently implemented usinga conventional general purpose or a specialized digital computer ormicroprocessor programmed according to the teachings of the presentdisclosure, as will be apparent to those skilled in the computer art.

Appropriate software coding can readily be prepared by skilledprogrammers based on the teachings of the present disclosure, as will beapparent to those skilled in the software art. The invention may also beimplemented by the preparation of application specific integratedcircuits or by interconnecting an appropriate network of conventionalcomponent circuits, as will be readily apparent to those skilled in theart based on the present disclosure.

The present invention includes a computer program product which is astorage medium (media) having instructions stored thereon/in which canbe used to control, or cause, a computer to perform any of the processesof the present invention. The storage medium can include, but is notlimited to, any type of disk including floppy disks, mini disks (MD's),optical discs, DVD, HD-DVD, Blue-ray, CD-ROMS, CD or DVD RW+/−,micro-drive, and magneto-optical disks, ROMs, RAMs, EPROMs, EEPROMs,DRAMs, VRAMs, flash memory devices (including flash cards, memorysticks), magnetic or optical cards, SIM cards, MEMS, nanosystems(including molecular memory ICs), RAID devices, remote datastorage/archive/warehousing, or any type of media or device suitable forstoring instructions and/or data (including remotely stored or executedprograms or data connected via Internet or other networks such aswireless, cellular, satellite, etc., to a device performing or using oneor more results of the invention (e.g., computer display, portabledevices, HDTV, or cinema theater system, etc)). Such instructions mayalso be divided between a network server and an end-user device, such asprocessing performed by a remote server and a digital cinema server toproduce signals necessary to drive the light sources and modulators at acinema theater according to any one or more teachings of the presentinvention.

Such signals may further include specialized processing andarchitectures to implement 3D and/or wide color gamut, as described, forexample, in issued U.S. Pat. No. 7,784,938 and co-pending U.S.application Ser. Nos. 11/804,602, 12/530,379 by the same inventor(Attorney Docket No.: DOL213US, DOL216US and DOL217US), and “PROJECTORAND PROJECTION SYSTEMS USING LASER LIGHT SOURCES AND RELATED METHODS FOR3D PROJECTION AND COLOR GAMUT IMPROVEMENTS,” Ser. No. 61/452,638 filedon Mar. 14, 2011 (Attorney Docket No. D10101USP1)

Stored on any one of the computer readable medium (media), the presentinvention includes software for controlling both the hardware of thegeneral purpose/specialized computer or microprocessor, and for enablingthe computer or microprocessor to interact with a human user or othermechanism utilizing the results of the present invention. Such softwaremay include, but is not limited to, device drivers, operating systems,and user applications. Ultimately, such computer readable media furtherincludes software for performing the present invention, as describedabove.

Included in the programming (software) of the general/specializedcomputer or microprocessor are software modules for implementing theteachings of the present invention, including, but not limited to,calculating laser energization levels and subsequent modulations in amulti-modulation system and the display, storage, or communication ofresults according to the processes of the present invention.

The present invention may suitably comprise, consist of, or consistessentially of, any of element (the various parts or features of theinvention, e.g., light sources, modulators, optics, and processing) andtheir equivalents. Further, the present invention illustrativelydisclosed herein may be practiced in the absence of any element, whetheror not specifically disclosed herein. Obviously, numerous modificationsand variations of the present invention are possible in light of theabove teachings. It is therefore to be understood that within the scopeof the appended claims, the invention may be practiced otherwise than asspecifically described herein.

What is claimed:
 1. A display, comprising: a light source; a displaymodulator; and a mid-point redirector configured to direct light emittedfrom the light source onto the display modulator in an overlappingpattern of illuminated areas; the mid-point redirector furtherconfigured to selectively re-direct light axially aligned toward a firstarea of the display modulator, the re-direction changing the alignmentof the light from the first area of the display modulator to a secondarea of the display modulator different from the first area; wherein thedisplay modulator is energized according to image data, a light fieldsimulation of the overlapping pattern of illuminated areas on thedisplay modulator, and selectively re-directed light.
 2. The displayaccording to claim 1, wherein the light selectively re-directedcomprises light re-directed from one or more first areas of the displaymodulator corresponding to one or more relatively dark portions of animage to be modulated to one or more second areas of the displaymodulator corresponding to one or more relatively bright portions of theimage to be modulated.
 3. The display according to claim 1, wherein themid-point redirector comprises an array of optical switches.
 4. Thedisplay according to claim 1, wherein changes in the mid-pointredirector result in corresponding changes in the light fieldsimulation.
 5. The display according to any of claim 1, furthercomprising a spreader between the light source and mid-point redirector,the spreader configured to diffuse the overlapping pattern ofilluminated areas.
 6. The display according to claim 5, wherein thespreader comprises reflective optical walls that direct the spread ofthe light in a manner that fills a predetermined illumination pattern onthe display modulator.
 7. The display according to claim 5, wherein thespreader comprises holographic material that diffuses the light at apre-determined angle or with a predetermined point spread function.
 8. Adisplay, comprising: an array of light sources configured to adjustenergy levels of the light sources based on control signals; a spreaderconfigured to spread light from the light sources and provide spreadillumination patterns of the light; a processor configured to determinean approximation of an image based on image data representing the image,calculate energy levels of the light sources based on the approximationof the image and the spread illumination patterns, and generate thecontrol signals for adjusting the energy levels of the light sources forproducing the approximation of the image through the spread illuminationpatterns; and a display modulator configured to receive the lightrepresenting the approximation of the image through the spreadillumination patterns and modulate the light to reproduce the image. 9.The display according to claim 8, wherein the control signals foradjusting the energy levels of the light sources for producing theapproximation of the image include control signals for locally dimming aportion of the array of light sources.
 10. The display according toclaim 8, wherein the control signals for adjusting the energy levels ofthe light sources for producing the approximation of the image includecontrol signals for locally dimming a portion of the array of lightsources corresponding to a relatively dark portion of the approximationof the image.
 11. The display according to claim 8, wherein theprocessor is further configured to generate modulation signals foradjusting the display modulator based on the image data and the adjustedenergy levels of the light sources.
 12. The display according to claim8, wherein the spread illumination patterns overlap on the displaymodulator.
 13. The display according to claim 8, further comprising: amid-point redirector between the spreader and the display modulator, themid-point redirector configured to selectively re-direct light fromtransmitting toward a first area of the display modulator totransmitting toward a second area of the display modulator differentfrom the first area.
 14. The display according to claim 13, wherein theprocessor is further configured to generate modulation signals foradjusting the display modulator based on the image data, a light fieldsimulation of the spread illumination patterns overlapped on the displaymodulator, and the light selectively re-directed by the mid-pointredirector.
 15. A method of content display, comprising: determining anapproximation of an image based on image data representing the image;adjusting energy levels of an array of light sources based on theapproximation of the image and spread illumination patterns associatedwith the light sources; spreading light emitted from the light sourcesfor providing the spread illumination patterns; receiving, by a displaymodulator, the light representing the approximation of the image throughthe spread illumination patterns; and modulating, by the displaymodulator, the light to reproduce the image.
 16. The method according toclaim 15, further comprising: performing a light field simulation of thespread illumination patterns;
 17. The method according to claim 15,wherein said adjusting energy levels of the array of light sourcescomprises: locally dimming a portion of the array of light sources basedon the approximation of the image and the spread illumination patternsassociated with the light sources.
 18. The method according to claim 17,wherein the portion of the array of light sources being locally dimmedcorresponds to a relatively dark portion of the approximation of theimage.
 19. The method according to claim 15, further comprising:selectively re-directing, by a mid-point redirector, light fromtransmitting toward a first area of the display modulator totransmitting toward a second area of the display modulator differentfrom the first area.
 20. The method according to claim 19, wherein thespread illumination patterns overlap on the display modulator.